[algogeeks] Re: No of tri-angles

2012-06-15 Thread shiv narayan
this is the running code to find no of triangles using brute force technique logic: in a triangle having sides a,b,c; then a+bc(if c is greatest side) correct me if i am wrong. #includeiostream #includeconio.h using namespace std; int max(int a,int b,int c) { return ((ab?a:b)c?(ab?a:b):c); }

Re: [algogeeks] Re: No of tri-angles

2012-06-15 Thread Amol Sharma
sry ignore the last comment for i wanted to say - your algo will work only when the numbers given are consecutive. -- Amol Sharma Final Year Student Computer Science and Engineering MNNIT Allahabad http://gplus.to/amolsharma99

[algogeeks] Re: No of tri-angles

2012-06-15 Thread shiv narayan
@anmol my algo will work even if nos are not in ascending order .correct me if i am wrong. On Jun 15, 7:45 am, Amol Sharma amolsharm...@gmail.com wrote: sry ignore the last comment for i wanted to say - your algo will work only when the numbers given are consecutive. -- Amol Sharma Final

[algogeeks] Re: No of tri-angles

2012-06-15 Thread enchantress
@amol True, but the question suggests they are . If they arent then it'll require sorting the array and then binary search for largest index for which a[index] a[i]+a[j] .. Then required triangles are index-j for looped values i and j. On Friday, 15 June 2012 20:15:26 UTC+5:30, Amol Sharma

[algogeeks] Re: No of tri-angles

2012-06-14 Thread enchantress
Use two loops: num_triangles = 0 for i:1 to (N-1)/2 for j:i+1 to i+jN num_triangles += N-(i+j) This gives values in increasing order such that cba (c,b,a being lengths of sides of the triangle) and sum of any two sides is greater than the third. Consider :

Re: [algogeeks] Re: No of tri-angles

2012-06-14 Thread payel roy
How come 1,2,4 gives a triangle ?? 1+2 4. On 14 June 2012 16:12, enchantress elaenjoy...@gmail.com wrote: Use two loops: num_triangles = 0 for i:1 to (N-1)/2 for j:i+1 to i+jN num_triangles += N-(i+j) This gives values in increasing order such that cba

[algogeeks] Re: No of tri-angles

2012-06-14 Thread enchantress
My bad.. it should be this: num_triangles = 0 for i:2 to N-2 for j:i+1 to N-1 num_triangles += i+j=N ? i-1:N-j This gives values in increasing order such that cba (c,b,a being lengths of sides of the triangle) and sum of any two sides is greater than the third.